Add batch Iceberg AddFiles yaml IT

sdks/java/io/iceberg/src/main/java/org/apache/beam/sdk/io/iceberg/AddFiles.java

@@ -557,20 +557,15 @@ public CommitFilesDoFn(IcebergCatalogConfig catalogConfig, String identifier) {
       this.identifier = identifier;
     }
 
-    @StartBundle
-    public void start() {
-      if (table == null) {
-        table = catalogConfig.catalog().loadTable(TableIdentifier.parse(identifier));
-      }
-    }
-
     @ProcessElement
     public void process(
         @Element KV<Void, Iterable<SerializableDataFile>> files,
         @AlwaysFetched @StateId("lastCommitTimestamp") ValueState<Long> lastCommitTimestamp,
         OutputReceiver<Row> output) {
       String commitId = commitHash(files.getValue());
-      Table table = checkStateNotNull(this.table);
+      if (table == null) {
+        table = catalogConfig.catalog().loadTable(TableIdentifier.parse(identifier));
+      }
       table.refresh();
 
       if (shouldSkip(commitId, lastCommitTimestamp.read())) {

sdks/python/apache_beam/yaml/tests/iceberg_add_files_batch.yaml

@@ -0,0 +1,88 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to You under the Apache License, Version 2.0
+# (the "License"); you may not use this file except in compliance with
+# the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+fixtures:
+  - name: TEMP_DIR
+    type: "tempfile.TemporaryDirectory"
+
+
+pipelines:
+  # Pipeline 1: Write dummy Parquet files
+  - pipeline:
+      type: chain
+      transforms:
+        - type: Create
+          config:
+            elements:
+              - {label: "11a", rank: 0, bool: true}
+              - {label: "37a", rank: 1, bool: false}
+              - {label: "389a", rank: 2, bool: false}
+              - {label: "3821b", rank: 3, bool: true}
+              - {label: "990c", rank: 4, bool: true}
+              - {label: "1024d", rank: 5, bool: false}
+        - type: WriteToParquet
+          config:
+            path: "{TEMP_DIR}/data/data"
+            file_name_suffix: ".parquet"
+            num_shards: 6
+
+  # Pipeline 2: Register our generated files in our Iceberg table
+  - pipeline:
+      type: chain
+      transforms:
+        - type: ReadMatchFiles
+          config:
+            file_pattern: "{TEMP_DIR}/data/data*.parquet"
+        - type: MapToFields
+          config:
+            language: python
+            fields:
+              path:
+                callable: "lambda row: row.path"
+                output_type: string
+        - type: IcebergAddFiles
+          config:
+            table: "default.table"
+            catalog_properties:
+              type: "hadoop"
+              warehouse: "{TEMP_DIR}/dir"
+
+    providers:
+      - type: python
+        config: { }
+        transforms:
+          ReadMatchFiles: 'apache_beam.io.fileio.MatchFiles'
+
+  # Pipeline 3: Read from Iceberg and verify the contents
+  - pipeline:
+      type: chain
+      transforms:
+        - type: ReadFromIceberg
+          config:
+            table: "default.table"
+            catalog_properties:
+              type: "hadoop"
+              warehouse: "{TEMP_DIR}/dir"
+        - type: AssertEqual
+          config:
+            elements:
+              - {label: "11a", rank: 0, bool: true}
+              - {label: "37a", rank: 1, bool: false}
+              - {label: "389a", rank: 2, bool: false}
+              - {label: "3821b", rank: 3, bool: true}
+              - {label: "990c", rank: 4, bool: true}
+              - {label: "1024d", rank: 5, bool: false}